Shone complex – surgical results

Shone complex – surgical results

Shone complex, originally described in 1963, [1] is combination of serial obstructions in the left heart at multiple levels. The original description included parachute mitral valve with congenital mitral stenosis, supra valvar ring in the left atrium, subaortic stenosis, and coarctation of aorta.

In the fetal life, a proximal obstruction is thought to predispose to a distal obstruction due to reduced distal flow. St Louis JD and colleagues published a retrospective review of twenty eight patients who underwent surgical correction at The Children’s Medical Center at the Medical College of Georgia, United States of America [2]. The mean age at presentation was fourteen days and almost half of them presented in the first week of life. Five of them presented in cardiovascular collapse while ten had NYHA (New York Heart Association) class III or IV functional status. Fifteen patients had mean trans valvar mitral gradient of 8 mm Hg or more. Six patients had supramitral ring and twenty six had coarctation of aorta. Ninety three percent survival at mean follow up of over six years (range one to sixteen years) can be considered as excellent. Moreover, they were in NYHA class I or II, which is even more heartening.

In general, because there is no corrective surgery for left ventricular inflow obstruction in children, mitral obstruction is usually the determinant of long term outcome [3]. Mitral lesions may be mild in many cases so that it can be left alone as well. Left ventricular outflow obstruction can be dealt with by Ross procedure or Ross-Konno procedure. A technical hitch while performing the Ross-Konno procedure of full root pulmonary autograft is that the implanted valve in the aortic position may exert pressure effect on the already narrow mitral complex which can cause a subclinical left ventricular inflow obstruction to progress to a clinically significant one. Obviously, this effect is likely to be more with a homograft than an autograft [4]. Simultaneous reconstruction of mitral and aortic annuli with bovine pericardial gussets for the successful management of late sequelae of Shone complex has also been described [5].

References

1. Shone JD, Sellers RD, Anderson RC, Adams P Jr, Lilliehei CW, Edwards JE. The developmental complex of “parachute mitral valve,” supravalvular ring of left atrium, subaortic stenosis, and coarctation of aorta. Am J Cardiol 1963;11:714–25.
2. St Louis JD, Bannan MM, Lutin WA, Wiles HB. Surgical strategies and outcomes in patients with Shone complex: a retrospective review. Ann Thorac Surg. 2007;84:1357-62.
3. Bolling SF, Iannettoni MD, Dick M 2nd, Rosenthal A, Bove EL. Shone’s anomaly: operative results and late outcome. Ann Thorac Surg 1990;49:887–93.
4. Aeba R, Okamoto K, Yozu R. Ross-Konno Operation for Patients with Shone Complex. Tex Heart Inst J. 2010; 37: 240–241.
5. Terry SM, Picone AL, Brandt B 3rd. Reconstruction of the mitral and aortic annuli for advanced management of the Shone complex. J Heart Valve Dis. 1999;8:343-5.